18
Time period - switch-on conditions
tDTO
:
Time period -
switch-on conditions
Adjustment range: 1 ... 100 s
in steps of 1 s
Factory setting: 60 s
The parameter
tDTO
is used for adjusting the time period
during which the switch-on condition
DT O
must be
permanentely fulfilled.
Filling time
tFLL
:
Filling time
Adjustment range:
1.0 ... 30.0 min
in steps of 0.5 min
Factory setting: 5.0 min
The filling time can be adjusted using the parameter
tFLL
.
During this period, the pump runs at 100 % speed.
Stabilization
tSTB
:
Stabilization
Adjustment range:
1.0 ... 15.0 min
in steps of 0.5 min
Factory setting: 2.0 min
The parameter
tSTB
is used for adjusting the time period
during which the switch-off condition
DT F
will be ignored
after the filling time has ended.
Drainback option
A drainback system permits the heat transfer fluid to drain
back into the holding tank when solar energy is not collected.
The drainback option will initiate the filling of the system
when solar loading begins.
If the drainback option
ODB
is activated, the pump will
operate at 100 % speed for the adjusted filling time
tFLL
in
order to fill the system with fluid from the holding tank. After
tFLL
, pump speed will go down to the adjusted minimum
pump speed
nMn
. The switch-off conditions will then be
ignored for the stabilization time
tSTB
in order to avoid the
system from shutting down prematurely.
If the function is activated, the menu items described in the
following (
tDTO
,
tFLL
and
tSTB
) have to be adjusted:
ODB:
Drainback option
Adjustment range: OFF / ON
Factory setting: OFF
Note:
A drainback system layout requires additional
components such as a holding tank. The drainback
option should only be activated if all components
required are properly installed.
Note:
When the drainback option
ODB
is activated, the
cooling functions
OCC
,
OSYC
and
OSTC
as well as
the antifreeze function
OCF
are not available.
If
OCC
,
OSYC
,
OSTC
or
OCF
have already been
activated before, they will be deactivated again
as soon as
ODB
is activated. They will remain
deactivated, even if
ODB
is deactivated later on.
Note:
When the drainback option
ODB
is activated, the
temperature differences
DT O
,
DT F
and
DT S
are set
to a fixed adjustment. Additionally, the adjustment
range and the factory setting of the collector
emergency shutdown temperature
EM
changes
(see the corresponding channel descriptions for
further information).
Previous adjustments made in these channels will
be overridden and have to be entered again if
ODB
is deactivated later on.
